The Sands of the Moon

The Sands of the Moon

"The moon is like a 4-billion-year-old desert," says Don Petit, one of the International Space Station Astronauts. Its surface is covered by dust and sand created by the impacts of meteorites. Surprisingly, just as sands and dusts from deserts here on Earth, when moistened in a terrestrial atmosphere such as that held within the Lunar Modules that visited the moon, moon dust smells. It is said, by many of the Apollo astronauts who came in contact with it, to smell like burnt gunpowder. In fact, Jack Schmitt, Apollo 17’s Geo-Astronaut, came down with the first recorded case of something we could call “moon fever,” an allergic hay fever sort of reaction to lunar dust.

Why moon dust would smell and cause allergic reactions is unclear: it certainly doesn't contain the organic molecules that create the odor in burnt gunpowder. Moon sands and dust are broken bits of moon rocks, or rounded particles of fused moon rocks melted by meteorite impacts, or an agglomeration of the two, that is, rock and mineral fragments held together by a glassy matrix. The rocky fragments are most often common moon minerals such as olivine, pyroxene and plagioclase, none of which smell on Earth. The fused glass dusts are the glassy equivalent of these minerals, that is, including the elements of silica, Fe, Mg and Al but lacking a crystalline mineral framework. Again, these have no inherent odors.

Gary Logfren, NASA’s lunar specimen curator, speculates that moon dust might even hold elements from the solar wind such as hydrogen, helium and other ions that evaporate in the lunar module or earth-like atmosphere giving off this unworldly odor. Jack Schmitt’s thinking, based in part on his nose’s itchy reaction, is that moon dust is chemically reactive.

I, too, once had an opportunity to examine moon dust and sands: to impress us beginning geology students, our prof (also working at NASA following the initial moon landing and working on lunar soils), brought some to our lab and let us look at it in a binocular microscope. I recall its appearance to this day: grey as grey can be, dry, ultra-dry, non-sticking particles that flowed more like a liquid than any sticky-dust or dirt that comes from Earth.

Possibly, it was this early exposure to “cutting edge” geology that lead me to become a geoscientist. I do not recall any odor or allergic reaction to the moon dust. Although, sadly, I am allergic to earth dust.

Thanks Annie R!

Photo by Gary Greenberg. More sands from the Moon under study by Gary and Dr Carol Kiely can be seen at:http://www.sandgrains.com/
Also recommend for the Lunar-tics among us:
http://science1.nasa.gov/science-news/science-at-nasa/2006/30jan_smellofmoondust/
http://www.jsc.nasa.gov/history/oral_histories/LofgrenGE/LofgrenGE_6-10-09.htm
http://www.universetoday.com/103274/moon-dust-could-engulf-lunar-rovers-especially-during-sunrise-and-sunset/